Absorbent personal care articles such as feminine hygiene products, adult care incontinence products and baby and child care diaper products are often placed in a user's undergarments, or between a user's body and outergarments to capture body fluids. Absorbent personal care articles traditionally include on their chassis at least a user-facing, topsheet or cover layer, that contacts the skin of a consumer during use, a garment-facing, backsheet layer that prevents leakage of body fluid through the backside surface of the article, and an absorbent core layer sandwiched between the topsheet layer and the backsheet layer, that absorbs and retains body fluid which is received through the topsheet layer. In feminine hygiene articles such as napkins, pads, and liners, adult care incontinence articles such as pads, inserts, briefs and diapers, and baby diapers, body fluids may have a tendency to flow off the article lateral side edges toward the user's legs in the crotch region. For feminine care pads, napkins, and liners, this directional movement is often near the article “wings,” “flaps,” or “tabs” (if present), the “wings,” “flaps,” or “tabs” being layer extensions that are used to hold the article to the user's undergarments.
To address such leakage, manufacturers of absorbent articles often incorporate additional side barrier features to provide fluid leakage protection. Such leakage protection is designed to prevent body fluids, such as urine, feces, or menses from running over or through the lateral side edges of the article, and subsequently staining a user's undergarments, outergarments or bedding. A traditional side barrier feature may incorporate an additional layer or structure (which provides elevation above the plane of the absorbent core layer within the article) for physically blocking the flow of fluid past the lateral side edges of the article. Examples of such additional structures include strips of absorbent or non-absorbent material, such as those described in U.S. Pat. No. 5,599,337 to Mccoy, U.S. Pat. No. 5,624,423 to Anjur et al., U.S. Pat. No. 5,713,885 to Jorgenson et al., and U.S. Pat. No. 5,807,367 to Dilnik et al., as well as those illustrated in CN 2436133Y. Such wall-like structures may be effective in reducing or eliminating side leakage, but require additional layer costs, and complicated manufacturing methods for cutting and/or placement of the structures on the article chassis. Further, such wall-like structures have parallel side edges which interfere with user comfort, being non-conforming to a user's inner thigh regions (crotch area) when in use.
Alternatively, such side barrier features may be formed from loops or folds in the topsheet layer or other additional layers on absorbent articles, as can be seen for example, in United States Publication 2001/020157 to Mizutani et al. As noted with the separate elevated structures previously described, such loops or folds may present complex manufacturing challenges and at additional costs. While targeted placement of walls only along certain regions of a lateral side edge is known, such as the discrete wall sections adjacent an article wing seen in U.S. Pat. No. 5,447,507 to Yamamoto, such additional structure requires relatively complex manufacturing steps and do not, in-and-of themselves, provide additional absorbency.
Other side barrier structures have employed elastic strands or elasticized portions along the side edges of an article, or alternatively, shrinkable strand material, to elevate portions of a topsheet layer of an article substantially above the plane of the absorbent layer, which provides for a close-to-body fit of the side barrier feature. Such elastic feature may be present in the article as it is initially obtained by the consumer. Alternatively, a shrinkable feature may be activated in an article only upon the occurrence of an event, such as later contact with body fluid or heat from a consumer during use. Such elastic or shrinkable side barrier features are frequently employed in both baby and child care absorbent articles, such as in diapers, as well as in feminine hygiene and adult care incontinence absorbent articles, such as in sanitary and adult care pad inserts. Elastic or shrinkable side barrier features are described for example, in U.S. Pat. No. 6,902,552 to VanGompel et al., in United States Publications 2012/296303 to Ng et al. and Mizutani noted above, as well as in European Publication EP0606082 to McDaniel. While these elastic or shrinkable features may be effective in blocking the flow of body fluids off of the article and/or containing the fluid in a cup-like configuration, such elastic or shrinkable materials are often constructed from expensive polymeric materials, which add significantly to the overall cost of the absorbent article, as well as to the complexity of the article manufacturing process. Even with the variety of side barrier features described above, there is still a need for effective side barrier features that are formed with absorbent structures, and that provide targeted barrier dimensions along specific portions of the lateral side edges of absorbent articles. There is a further need for barrier structures which do not incur expensive material costs or require complex manufacturing steps for their implementation. For example, there is a need for such barrier features which may be formed from previously existing non-barrier layers of an article.
Embossing channels or grooves have also been used to create wall-like, topographical features, in order to slow the movement of fluid to, or past the lateral side edges of an article. An example of such embossing channels may be found in U.S. Pat. No. 5,795,344 to Chappell. Such embossing channels or grooves may be of any number of shapes and/or patterns, may be located in a number of positions on the article, such as the rectangular, peripherally-placed channel in Chappell, or alternatively arcs, such as those illustrated in U.S. Pat. No. 6,410,822 to Mizutani. Still further known embossment channel shapes may include racetrack or dogbone designs, or discrete patterns. However, even with such variety of embossed channel shapes and embossment positions, there is a need for enhanced barrier structures which offer both non-uniform dimensioned absorbent functionality, above the plane of the main absorbent layer of an article. Such non-uniform dimensioned absorbent functionality could provide for targeted barrier protection in certain areas/regions along an article side edge, without wasting article construction materials and without adding additional material costs to an absorbent article.
Finally, “compound” absorbent pads are also known in the feminine hygiene area. Such are exemplified by international publication WO1998/43585 to Chatterjee. However, even with such compound pads, there is still a need for pads with absorbent barriers that are targeted to provide enhanced protection along high-leakage areas of such pads, and which are cost effective (not requiring extra materials or complex construction steps).